Daqing Oilfield is the largest oilfield in China. It provides 50% of China's yearly total oil production of 120 million tons. The no. 6 production plant of Daqing Oilfield is the pioneer in computer application for petroleum production in China. In 1981, the No. 6 production plant bought its first computer. In 1985, based on the comprehensive applications of computers, a network was built to connect all the information sources and decision making agents including production teams, technical service teams, geology teams, testing teams, production management and control offices. Later on, the operation system was put into the network. According to the specific situations in the oilfield, over 300 softwares were developed and their application was very fruitful. With the application of computers, oil production increased by over 1%, production cost decreased by 15%. Energy consumption and equipment damage are decreased. After the computerization in the oilfield, the no. 6 production plant gets economic benefits over 30 million Yuan (5 million U.S. dollars). Introduction Computer systems with their powerful hardwares and effective software packages are becoming more and more important to the petroleum industry. As early as in 1969, a computer system was successfully used to optimize oilfield production operations. This computer system is basically a data-gathering system. P. 345^

The purpose is to study the handling stability and energy saving mode of energy saving electric vehicles. First, the differences between electric vehicles and traditional fuel vehicles are analyzed. Moreover, based on active safety technology, the control stability, handling stability and driving safety of electric vehicles are improved. Then, based on the vehicle dynamics theory and the proposed assumptions, the modular electric vehicle dynamics model is established, including the wheel model, tire model and driver model, which can effectively control the error of the vehicle model and reduce the difficulty and complexity of vehicle modeling. Next, based on the model predictive control theory, the vehicle steady-state control strategy is established, which can predict and control the state of the electric vehicle in the compound condition and improve the control stability of the vehicle. Finally, the vehicle dynamic model and steady-state control system are simulated and tested. The experimental results show that the simulation results of the established dynamic model of the electric vehicle in angle step condition and single line shifting condition are consistent with the results of professional software, which shows that the established dynamic model can accurately describe the dynamic state of electric vehicle and provides the basis for the research of vehicle stability control strategy. Experimental results of the control strategy under the condition of double line shifting show that the designed control strategy can accurately track the state of the system and constrain the deviation in a small range, so as to ensure the driving stability of the electric vehicle. This exploration provides a reference for the study of dynamic analysis and handling stability control strategy of electric vehicles.

With the further exploration of oil and gas, we have to search for new resources which buried in deep strata, and most of the deep and ultra-deep wells are categorized in high-pressure/high-temperature (HPHT) wells. The problem of high temperature and the challenge to the existing downhole equipments are becoming increasingly prominent, where the drilling depth is severely restricted. The conventional measurement while drilling tools with common electronics will experience very high failure rates at these conditions. One of the solutions is called the active cooling technology, which can transfer the heat from electronics system to downhole environment. By this way, the temperature control of downhole instrument circuit system is realized. The active cooling technology is expounded in this paper, expecially about the principles and development status of each system. After evaluating and analyzing the characteristics of this technology, the function of heat transfer and constituent elements for the cooling system are summarized. The study from this work demonstrates the future work for downhole cooling technology: large refrigeration capacity, small size, strong adaptability and modularization.

To increase reservoir-encounter drilling ratio while horizontal directional drilling, this paper presents a novel LWD tool based on the high frequency electromagnetic wave, which can get the accurate distance between the drilling tools and reservoir boundary. While horizontal directional drilling in the reservoir, the LWD tool mentioned transmits a modulated single-frequency pulse, the pulse width is about 10ns and the central frequency is about 350MHz, by the transmitting antenna. The high frequency electromagnetic wave is reflected on the interface of the reservoir and the cap because of the dielectric difference. The reflected wave can be captured by the receiving antennas and then be processed in the designed algorithm aiding in ranging the distance of the reservoir boundary in real time. A 2.0*1.0*0.7 meters clay sand, concrete ground and a saline bag with the conductivity in 60mS/cm are designed to simulate the situations likely to be in real horizontal directional drilling operations and to evaluate the detection capability of the LWD tool in a controlled situation. Under the different conditions and distances, the measurement range of the LWD tool is about 0.7∼2.0 meters and the accuracy is less than ±3 centimeters, a high accuracy for geosteering in horizontal directional drilling, which will be greatly helpful to keep the drilling bit drilling in the optimum position of oil or gas reservoir all the time to increase the reservoir-encounter drilling ratio.

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